The present invention relates to a cantilever of a scanning probe microscope capable of detecting both of near-field light and magnetic field and a manufacturing method therefore, and a thermal assist type magnetic head device inspection method and an apparatus for inspecting a thin-film thermal assist type magnetic head device by detecting near-field light and micro-scale magnetic field using the scanning probe microscope.
As a next-generation hard disk magnetic head, a thermal assist type magnetic head device disclosed in Japanese Patent Application Laid-open publication Nos. 2010-182394, 2011-86362 and 2011-113595, is studied, near-field light generated from the thermal assist type magnetic head device is within a range of 20 nm or narrower width from the head device. This width determines a write track width of a hard disk. An inspection method for the intensity distribution of the near-field light, the surface shape of a light emitting member, and the positional relation between the near-field light and the write magnetic field, upon actual operation, is an unsolved important problem.
On the other hand, based on a scanning probe microscope (SPM) inspection technique using a cantilever having a magnetic probe, a method for inspecting a write magnetic field of a thin-film magnetic head device in a raw-bar state is disclosed in Japanese Patent Application Laid-open. Publication No. 2009-230845.
In the method disclosed in Japanese Patent Application Laid-Open Publication No. 2009-230845, it is possible to measure only the track width of the write magnetic field of the magnetic head device. However, there is no consideration of inspection of near-field light generated by a thermal assist type magnetic head device as a next-generation hard disk magnetic head device, or the surface shape of a near-field light emitter, the positional relation between the near-field light emitter and a write magnetic field generator, and the like.
Further, Japanese Patent Application Laid-open Publication No. 2009-230845 discloses inspecting the performance of the magnetic head device in a raw-bar state cut oat from a wafer. It is desired to handle the occurrence of fault in the thermal assist type magnetic head device upstream of the manufacture process and to prevent frequent occurrence of defective products by performing inspection at an early stage of head manufacturing, i.e., in raw-bar state, with respect, to the thermal assist type magnetic head device.